Fire extinguisher and other pumplike device



Aug. 28, 1934, B. v. HEITMULLER ET AL FIRE EXTINGUISHER AND OTHER PUMP LIKE DEVICE Filed OCL. 2l. 1932 ATToRNl-:Y

Patented Aug. 28, 1934 l' -'if `liuto1EzrifiNGUIsHE-R AND OTHER PUMP-` UKEDEVICE i Application" october "21,

19a-z, serial No. 638,922

i This invention relates to improyement'sfinofire extinguishers, pumps, syringes and similardevices in which a desired movement of 4a fluid is con- `tlcilled'bya pjstonmeans. o .V

e This invention has for its -principal object to 5 provide ina reextinguisher, pump, syringe yorthe like a novel formandconstruction of ,plunger or piston therefor whichis back-pressure leak-proof, `and one; which is adapted to lresist deteriorating or damaging effects of chemical fluids such as `carbon tetrachloride especially.` 3 Y Thisinvention hasfor a=further.0bjebi20 provide a novel construction of portablere extinguisher provided `with a spring-actuated plungeror piston,` and a novel self-locking .but 15 manually reieasable detent meansior retaining said .plunger or piston normally immovable under `the tensional thrust of the actuating spring therefor. i .f l, i This invention has for a` further object to pro- 20 `'vide 'in a portable fire extinguisher-a .novel discharge nozzle therefonland also. a novel means vthrough which the extinguisher may be refilled afteruse. f u 1 .f

`Other objects orthis invention, not atl this time more particularly enumerated, lwillV be understood from the following" detailed descriizition:of` the same. t i An illustrative embodimentv ofthe Vpresent invention is shown-in the accompanying drawing, in Whichn.. Y if f ,1

Fig. 1* is a sectional -vi'ewofa nre extinguisher according to this inventiomthe Vnovel-1 piston structure being shownfinside elevationa'nd as normally subjected to the restraining actionof detent means therefor;` 2'is asimilar view, showingthe pistonl in vertical section, A'and also showing the detent means released 'to subject the piston to thrust of its actuating-spring; Fig. Bis a fragmentary sectional View illustratingthe self*- locking operation of-vs'aid-dete'nt means in'progress; FigA is a horizontal section, taken on line 4 4 in Fig. l showing the detentr means locked; Big5-is a horizontal view, taken on 1ini15-5 irrFig'.- 3; Fig. 6 is an enlarged vertical 'sectional View of the discharge nozzle of'the extinguisher as closed; and Fig. 'l is a vfragrnent'ary View Aofthe nozzle'in open condition. l e l 1 i Similar characters of reference are employed in the above-describedviews,.to indicate corresponding-Darts; A I" f i Referring to said drawing, the referencechar.- acter loindicates the cylinder or casing; of the devioepth'e `same being -closed-.at its .top by an y upper end cap 11 and at its bottom by aiower end capii` :Said lower end cap .1,2 is :provided with a. central boss 13 providedfwith an inter- 'being assured by the engagement of 'cooperating ,stop .pins 26 and 27 respectively carried by said nozzle body. 154 and `said closure member 23. .When said closure member 23 is turned to screw lopen position in which the port 25 thereof is nally screw-threaded opening to receive the externally threaded stub 14 of a nozzle body 1,5.

Aroundthe stub 14'J andbetween the external side .of'said `lower end cap 1,2 and said nozzle body 15 is interposed a resilient packing washer 1'7 to D render thejointbetween the latter parts leakproof. Said nozzle body l5 is provided 'at its 'lower free end with an externally screw-threaded neck 184 having a closed terminal wall 19. 'The exterior surface of said terminal wall 19 is of ec- 65 centrically formed conical contour having a high 'off-set side 20. Extendingthrough said stub 14,

nozzle `body and into said neck 18 is an axial discharge passage 2l, and provided in and through the high ofi-set side 20 of` said terminal wall 19 'm iis a discharge orifce`22 which communicates with saidfdischarge passage21. Threaded onto said .neck 18 is a closure member23 having an internal conical seat 24 `to cooperate` with said terminal wall 19 of said neck 18. Formed in said closure member 23 is a centrally off-set discharge port "25,V which by turning said `closure member 25Y may berbroughtminto alignment with said discharge orice 22, the alignmentr of said orice and port vinto tight sealing` relation to the high oir-set side l.20. of `the terminal 4wall 19 in which is located the D0 `discharge orifice 22 by. a Wedging action which .effectively and securely stops off the latter against 'escape of liquid from the interior ofthe cylinder `of casing l0. '.Proojecting, from'the side of said nozzle body 15 is an externally screw-threaded 95 ,extension 23 having va passage 29 therethrough 4which communicates ,with the discharge passage 21 of said nozzle body 15. At the outer end of said., passage `29 is a port 30 normally closed by ,a spring-pressed inwardly opening ball orcheck- Y-valve 3l A removable sealing cap 32 is engaged :on lthe outer end of said extension 28. Y

-' i The reference character? indicates l'generally a pistonor plunger member which ismovable axially within the interior of said cylinder or casing 10, the detailocharacter and construction of which will be lhereinafter more particularly set forth. Connected with the upper side of said pis- .ton is a seating cup 33 in which is engaged the o `lower end ot a compression-spring 34which is -110 arranged within the upper end of the cylinder or casing 10 between the piston and the end cap l1, and which, when free to react, operates to move the piston or plunger downwardly through the cylinder or casing 10 with discharging effect upon the fluid with which the interior of the latter, below the piston, is charged.

Secured centrally within the seating cup 33 to extend upwardly therethrough and outwardly from the upper open end thereof is a coupling member comprising, a base 35 and a pair of laterally spaced oppositely and outwardly yieldable spring arms 36, respectively provided at their upper free ends with in-turned and preferably somewhat downwardly inclined catch-lugs or lips 37. A detent means to cooperate with said coupling member is connected with the upper end 11 of the cylinder or casing 10. This detent means comprises a detent pin 38 having at its upper end a shank 39 of reduced diameter. Said Ishank 39 extends upwardly and outwardly ythrough a central opening in said upper end cap 11, which opening is provided at its margin with notches 40 providing air passages or vents. Suitably secured to the exteriorly projecting end of said shank 39 is a knob 41, and arranged between said knob and the end cap 11 is a light compression spring 42, which,.when the detent pin is free or disengaged from the piston coupling member lifts the same axially to raise a sealing disc 43 carried at the lower end of the knob 4l out of closing and sealing relation to the air passages or vents 40 of the end cap 11. Said detent pin 38 is rotatable about its longitudinal axis. Adjacent to its lower or inner end, said detent pin is provided on opposite sides with recesses to receive the catch-lugs or lips 37 of said piston coupling member, whereby the latter may engage retaining shoulders 44 located at the lower sides of said recesses. Below said retaining shoulders 44, the lower extremity of said detent pin is formed to provide an inverted conical spreader member 45. Formed on opposite sides of said spreader member 45 are helical or ascending spiral rotator guides 46 respectively leading to the respective retaining shoulders 44.

When the cylinder or casing 10 is charged with a suitable re extinguishing liquid, such, for example, as carbon tetrachloride, the piston P occupies an upwardly raised position within the cylinder or casing, with the spring 31 fully compressed between said piston and the cap 11, and with the catch-lugs or lips 37 of the piston coupling member engaged by the retaining shoulders 44 of the detent pin 38, as shown in Fig. 1. Under such conditions, the powerful tension of the compression spring 34, transmitted through the piston and its coupling member to the detent pin 38, exerts a strong downward pull upon the latter, overcoming1 the tensional reaction of the relatively weak spring 42, whereby the knob 41 is pulled down to tightly press the sealing disc 43 into closing engagement with the air vents 40,

kas is also shown in Fig. 1.

When it is desired to discharge the re extinguisher liquid from the cylinder or casing, the piston P is released from the detent means, lso as to free the lcompression spring 34 so that its stored tension may operate to move downward the piston against the body of liquid below the same upon opening the nozzle at the discharge end of the cylinder or casing. To release the detent means, the knob 41 is given a half turn, thereby rotating the detent pin 38 so as to spread apart the catch-lugs or lips 37 of the piston coupling member, while at the same time removing the retaining shoulders 44 from beneath the latter, whereupon said piston coupling member may slip downwardly off of the detent pin, as shown in Fig. 2. When the detent pin is thus released, its spring 42 operates to lift the detent pin and knob 41 to carry the sealing disc 43 away from thel air vents 40, so that atmospheric air may enter the cylinder or casing interior above the piston during the descent of the latter, thereby breaking any vacuum which might tend to impede the discharging movement of said piston. In order to assure inward passage of air beyond the vents 40 unimpeded by the shoulder of the detent pin formed at the juncture of the shank 39 therewith, said shoulder is provided with suitably disposed grooves or channels 47 through which ingoing air may pass.

After the content of the cylinder or casing is discharged, the piston may be returned to normal initial raised position with the spring 34 compressed behind the same, and thereupon again operatively engaged with the detent means preparatory to refilling the device with fire extinguishing liquid. One method of performing these operations is as follows:

The discharge nozzle being closed, the cap 32 is removed from branch extension 28 thereof, and the latter is suitably coupled in communication with a source of compressed air. The air under pressure is thereupon admitted past the checkvalve 31 through the passage 29 and thence into the interior of the cylinder or casing below the piston P. The pressure of the air thus introduced drives upwardly the piston P with recompressing effect upon the spring 34. The air above the piston is displaced from the cylinder or casing interior through the channels 47 and open air vents 4 0. As the piston approaches the upper limit of its movement within the cylinder or casing, the lugs or lips 37 of its coupling member spring arms 36 which carry the same. As the lugs or lips 37 ride upwardly they will be carried into engagement with said spiral rotator guides 46 along'which they will travel. The inward pressure of said lugs or lips against the guides as they travel upwardly in contact therewith will produce a rotative movement of the detent pin, whereby the latter will be turned to align its retaining shoulders 44 in the path of said lugs or lips, so that by the time the latter pass beyond the spreader member 45 the recesses bounding the retaining shoulders 44 will be positioned to receive the same, and consequently said lugs or lips under the tension of the spring arms 36 will snap over said retaining shoulders 44 and into retained or coupled engagement therewith whereby the piston is normally held iny raised position against the tension of spring 34.

After the piston is reset as above described,

the interior of the cylinder or casing may be refilled with liquid. This is accomplished by unscrewing and removing the discharge nozzle, and thereupon introducing the liquid through the bore of the boss 13 of the lower end cap 12, after which the nozzle is replaced.

Instead of using air to drive back the piston P, i

tof theA cylinder or casing walls.

experienced in ytheV use of carbon tetrachloride in plunger discharged fire extinguishers, due to 'the fact that this substance Vquickly' attacks leather, rubber and like' washers commonly employed in the piston or plunger structures; with "the result that not only is the effectiveness of the piston or plunger impaired, but'its resistance tot back-pressure is quickly overcome with consequent undesired leakage of the liquid pastthe piston or plunger.` .It is, therefore, one of the `most important objects of this invention to prolvide'a piston or plunger structure per se which s arranged.V It will be obvious that a piston or plunger of this character is not only highly de- "sirable for use in fire extinguishers generally and of the kind above described, but is also useful in lany type of similar pump or syringe-like device desired to operate upon a carbon tetrachloride liquid.

` The novel piston or plunger structure, according to this invention, comprises a pair of hanged felt `washers 48 and 49 spaced apart and arranged 'with their peripheral flanges in opposed relation and adapted to firmly engage the interior sides s The bodies of said washers are respectively reenforced and sup- "ported along their downwardly facing or under sides by the respective steel discs 50 and 51, and the washers and discs are maintained in vertically spaced relation by a spacing sleeve 52 centrally 'disposed therebetween. In the space between the opposed washers 48-49 is disposed a resilient body of ller material 53 comprising, broadly, a mixture of gelatin, glycerine and Igraphite coagulated to provide a form retaining mass. The washers and their flanges are 'themselves likewise impregnated with a mixture of gelatin and glycerine to render the bodies of the same impervious to liquid carbon tetrachloride. To retain the elements of the piston structure in operative mutually assembled relation, and likewise in as- A'sembledconn-ection with the seating cup 33 and the coupling member which is cooperative with the detent means of the above described re extinguisher device, a tie bolt 54 is passed upwardly and centrally through the washers and discs and through the intermediate spacing sleeve, and thence through the'body of th-e seating cup 33 andthe base'35 of said coupling device, a retaining nut 55 being engaged on the projecting threaded end of said tie bolt and screwed home to thereby tightly bind the specified parts together.

For the production of the body of filler material 53, we use substantially the following formula:-

About of gelatin is dissolved in 10% of water, and to this is added 45% of glycerine and of graphite. The mixture is thoroughly agitated to intermix these ingredients, and then poured in a mold for coagulation and shaping to the desired body conformation. When removed from the mold, the body produced fur nishes a resilient mass of a consistency someresistant to deterioration or alteration in the presence of carbon tetrachloride, but is sufficiently resilient asto be readily responsive to squeezing pressure whereby its peripheral surfaces are 4iirmly pressed against the sides of the cylinder or casing-wals to form a leak-proof contact therewith past which the carbon tetrachloride*L cannot force itself; the `more pressure exerted the tighter will be such contact. In thelcomposition: gelatin provides the bodying material,

'the glycerine prevents the mixture from hardening, and the graphite providesa lubricating element.

In Vorder to render the washer elements them- "selves impervious to or impenetrable by liquid lcarb-on tetrachloride, `the same are impregnated with a solution of 30% gelatin dissolved in 25% vof water, to which is added of glycerine.

The above proportions of ingredients for the 'filler material and for the washer impregnating solution are merely illustrative, and are subject to more or less variation within reasonable limits. With respect to the iiller material, the graphite may be omitted in cases where its lubricating functions is not deemed necessary. i

Piston or plunger constructed in accordance with the above description thereof are of great durability, are adequately resistant to back pressure leakage, and will not deteriorate in contact with carbon tetrachloride, therefore rendering the same especially useful in plunger discharged fire extinguishers and other pump-like devices desired to operate with tetrachloride liquid.

We are aware that many changes could be Vmade and many apparently widely different ernbodiments of this invention could be produced without departing from the scope thereof, and consequently it is intended that all` matter contained in the above description or shown in the accompanying drawing shall be interpreted as `illustrative and not in a limiting sense.

fluid, spring means for actuating said piston, a l

rotatable detent pin at the opposite end of `said cylinder, aresilient bifurcate coupling means carried by said piston, said pin and coupling means being adapted to `interlockin oneV angular, position`of said pin and not to interlock in another angular position of said pin, conical spreader means on said detentpin having rotator guides vengageable by said coupling Ymeans for automatically rotating said pin `to operative holding position when said coupling means is movedA into l contact therewith, and manipulatable means for manually rotating said detent pin to releasing position.

2. In a device of the kind described, the combination with a cylinder having a discharge nozzle at one end and adapted to contain a uid to be discharged, of a piston for discharging said fluid, spring means for actuating said piston, a rotatable detent pin within the opposite end of the cylinder, said detent pin having a shank jour- 'i naled in and extending through said opposite end of the cylinder, a knob on the external end of said shank, a sealing disc carried by said knob, said cylinder end having air vent means closable by said sealing disc, a coupling means carried by said piston, means on the interior end of said detent pin engageable by said piston coupling means for automatically rotating said pin to operative holding position when said piston coupling means is moved into contact therewith, and

. spring means between said knob and cylinder end to outwardly move said detent pin with said knob y and sealing disc to open said air vent means when said detent pin is released from said piston coupling means.

3. In a device of the kind described, the combination with a cylinder to contain a fluid to be discharged, a discharge nozzle at one end of said cylinder having means to open and close the same.

a piston movable in said cylinder, spring means `coupling means being adapted to interlock in one angular position of said pin and not to interlock in another angular position of said pin, a conical spreader means on said detent pin having rotator guides engageable by said coupling means, and manipulatable means for releasing said detent means.

4. In a device of the kind described, a cylinder having a discharge means at one end, a piston, spring means for moving said piston toward the discharge end ofv said cylinder, a detent means for holding said piston at the opposite end of said cylinder, said detent means comprising a rotatable detent pin, a resilient bifurcate coupling means, said pin and coupling means being adapted to interlock in one angular position of said pin and not to interlock in another angular position of said pin, a conical spreader means on said detent pin having rotator guides engageable by said coupling means, and manipulatable means for releasing said detent means.

5. In a device of the kind described, the combination with a cylinder to contain a fluid to be discharged, a discharge nozzle at one end of said cylinder having means to open and close the same, a piston movable in said cylinder, spring means for actuating said piston towardk the discharge end of said cylinder, said nozzle having an inwardly entering branch passage for delivering a uid under pressure into said cylinder whereby said piston may be moved against its actuating spring toward the opposite end of said cylinder, an outwardly closing check-valve in said branch passage, a rotatable detent pin within said opposite end of the cylinder, said detent pin having a shank journaled in and extending through said opposite end of the cylinder, a knob on the external end of said shank, a sealing disc carried by said knob, said cylinder end having air vent means closable by said sealing disc, a coupling means carried by said piston, means on the interior end of said detent pin engageable by said piston coupling means for automatically rotating said pin to operative holding position when said piston coupling means is moved into contact/ therewith, and spring means between said knob and cylinder end to outwardly move said detent pin with said knob and sealing disc to open said air vent means when said detent pin is released from said piston coupling means.

6. A device of the kind described as dened in claim 1, wherein the piston comprises spaced oppositely facing flexible washers, relatively rigid discs for supporting and reenforcing said washers, and a resilient iiller body intermediate said washers comprising a coagulated mixture of gelatin and glycerine.

'7. A device of the kind described as defined in claim l, wherein the piston comprises spaced oppositely facing flanged felt washers impregnated with a mixture of gelatin and glycerine, relatively rigid discs for supporting and reenforcing said washers, and a resilient ller body interymediate said washers comprising a coagulated in claim 2, wherein the piston comprises spaced oppositely facing flanged felt washers impregnated with a mixture of gelatin and glycerine, relatively rigid discs for supporting and reenforcing said washers, and a resilient ller body intermediate said washers comprising a coagulated mixture of gelatine, glycerine and graphite.

10. In a device of the kind described as defined in claim 5, wherein the piston comprises spaced oppositely facing anged flat washers impregnated with a mixture of gelatin and glycerine,

relatively rigid discs for supporting and reenforcing said washers, and a resilient ller body intermediate said washers comprising a coagulated mixture of gelatine, glycerine and graphite.

BERNHARD V. HEITMULLER. JACOB F. LOEFFLER. 

